CROSS-REFERENCE TO RELATED APPLICATION
BACKGROUND OF INVENTION
[0002] Single-use biocontainers 10 as shown in FIG. 1 are manufactured for use in conjunction
with hardware designed around a platform 12 that oscillates in a rocking or seesaw
motion, as for example described in
U.S. Patent No(s). 6,190,913,
6,544,788 and
7,195,394, the contents of which are fully incorporated herein by reference. This rocking motion,
typically on the order of 12 to 20 degrees total sweep at a rate of 4-25 cycles per
minute, is transferred to the biocontainer about an axis 14 which in turn imparts
motion to a fluid and/or gas contained therein. For convenience the term "fluid" as
used hereafter after refers to a fluid, or a gas, or to the combination of a fluid
and a gas. The imparted fluid motion is often used to accomplish unit processing steps
within the biopharmaceutical industry, e.g. mixing or cell culture operations. The
latter of these examples can require extended processing times on the order of one
week to three months plus during which the oscillatory rocking motion is repeated
constantly. These extended operating periods subject the biocontainer to high cyclical
stress loads which can lead to breaches in the fluid containment area.
[0003] The biocontainers manufactured for use in conjunction with the aforementioned rocking
platforms are typically single-use bags of construction such as shown in FIG. 2A.
It should be noted that "bag(s)," "biocontainer(s)" and "biocontainer bag(s)" are
used interchangeably herein. Representative biocontainers are two-dimensional in nature
and are manufactured from two sheets (films) 16A, 16B of polymeric film 16 having
dimensions (H1 x W1) that are welded together along weld lines 18, 20, 22, 24, 26
and 28 to create a contained seal geometry. The welds along the weld lines form seams.
Thus, the terms "weld lines" and "seams" are used interchangeably herein to refer
to the area of bonding between the two sheets of polymeric film. These biocontainers
contain porting 29, for fluid ingress and egress as well as gas exchange, which are
welded within a fluid containment area 16 (H2 x W2) defined between weld lines 18,
20, 22 and 24. The weld lines form seams. Additionally, the biocontainers include
rigid support rods 32 at each end which are sealed into segregated areas 33 of the
biocontainer (H3 x W3) defined between weld lines 20, 26, 18 and 22, and 24, 26, 18
and 22, respectively. The support rods are used to help secure the biocontainer to
the rocking platform. The rocking platform includes at least two clamps, such that
each clamp clamps on the segregated areas and specifically the rod in such areas for
securing each end of the biocontainer in place.
[0004] When the biocontainers are deployed, i.e. secured to the rocking platform and filled
to capacity with a fluid, three distinct zones 34, 36 and 38 form. A first zone 34
also referred to herein as "Zone 1" is a two-dimensional zone in that it remains relatively
flat. This area of the flexible single-use biocontainer is constrained by the rocking
platform clamp and thus retains it two-dimensional "flat" shape. A second zone 36
referred to herein as "Zone 2" is a transitional zone. In this area, the biocontainer
shape transitions between a generally two-dimensional shape at one end and the fully
developed three-dimensional shape at its other end. A third zone 38 also referred
to herein as "Zone 3" is a three-dimensional zone. In this zone, the biocontainer
has developed its three-dimensional shape and has a cross-sectional shape along its
length which is oval as a result of the fluid fill volume.
[0005] With the current biocontainers depicted in FIG. 2A, folding, crumpling and/or other
undesirable film shapes can occur in Zone 2, i.e., in the transitional zone, due to
geometry constraints associated with the transition between the two-dimensional end
portion and the three-dimensional center portion. These undesirable film shapes create
stress concentrations which when combined with the cyclical stress associated with
the oscillatory motion of the fluid within the biocontainer, serve to decrease the
service life of the biocontainer. Premature failures are believed to be due to either,
a stress crack in the polymeric film material at a stress concentration point, or
abrasion between the two films at a contact point. Both of these failure mechanisms
manifest themselves in a repeatable nature in the four identified areas D in the transitional
zones 36 of the current biocontainers and are directly attributable to the aforementioned
undesirable film shapes in the transitional zones (Zones 2).
SUMMARY OF THE INVENTION
[0006] In an exemplary embodiment a biocontainer is provided including a first flexible
wall, a second flexible wall opposite the first flexible wall, a first end, a second
end opposite the first end, a third end extending between the first and second ends,
a fourth end extending between the first and second ends and opposite the third end,
and a first relief section extending from the first end, wherein the first relief
section is connects the first flexible wall to the second wall. In another exemplary
embodiment, the first flexible wall is separate from the second flexible wall and
is connected to the second flexible wall. In yet another exemplary embodiment, the
first flexible wall is connected to the second flexible wall along at least one of
the ends. In a further exemplary embodiment, the first relief section includes a separate
member connected to the first flexible wall and to the second flexible wall. In yet
a further exemplary embodiment, the first relief section is formed by connecting the
first flexible wall directly to the second flexible wall. In one exemplary embodiment,
the first relief section begins and ends at the first end. In another exemplary embodiment,
the biocontainer also includes a second relief section, along which the first wall
is connected to the second wall, proximate the fourth end beginning from and ending
at the first end, a third relief section, along which the first wall is connected
to the second wall, proximate the third end beginning from and ending at the second
end, and a fourth relief section, along which the first wall is connected to the second
wall, proximate the fourth end beginning from and ending at the second end. In yet
another exemplary embodiment, each of the relief sections is semi-circular in plan
view. In a further exemplary embodiment, when the bag is filled with a fluid, the
biocontainer has a depth as measured between the first and second walls, wherein the
depth increases from each of the third and fourth ends in a direction along each of
the first and second ends transitioning between minimum or no depth at each of the
third and fourth ends to an expanded depth at a distance from each of the third and
fourth ends, wherein each of the first, second, third and fourth seams are located
along a length within the distance. In one exemplary embodiment, the expanded depth
is a maximum depth. In a further exemplary embodiment, each of the first, second,
third and fourth relief sections are curved or define a geometric shape in plan view.
In yet a further exemplary embodiment, each of the first, second, third and fourth
relief sections intersects its corresponding first or second end at an external angle
greater than 90°. In another exemplary embodiment, the biocontainer also includes
a seam extending from the third to the fourth ends and being spaced apart from the
first and second ends. In yet a further exemplary embodiment, the first relief section
aids in the mixing of a fluid within the biocontainer. In one exemplary embodiment,
a seam is defined along each of the ends connecting the first flexible wall to the
second flexible wall. In another exemplary embodiment, a single piece of flexible
material is bent over itself and connected along a seam to form the first flexible
wall and the second flexible wall.
[0007] In yet another exemplary embodiment, the first flexible wall is separate from the
second flexible wall and the biocontainer further includes a first seam along the
first end along which the first wall is connected to the second wall, a second seam
along the second end along which the first wall is connected to the second wall opposite
the first seam, a third seam along the third end along which the first wall is connected
to the second wall and extending between the first and second seams, a fourth seam
along the fourth end along which the first wall is connected to the second wall and
extending between the first and second seams and being opposite the third seam, and
a fifth seam defining the first relief section, along which the first wall is connected
to the second wall, proximate the third seam beginning from and ending at the first
seam, wherein the biocontainer has a length along the first seam and a width along
the third seam as measured between the third and fourth seams, wherein each seam connects
the first flexible wall to the second flexible wall. In a further exemplary embodiment,
the biocontainer also includes a sixth seam, along which the first wall is connected
to the second wall, proximate the fourth seam beginning from and ending at the first
seam, a seventh seam, along which the first wall is connected to the second wall,
proximate the third seam beginning from and ending at the second seam, and an eight
seam, along which the first wall is connected to the second wall, proximate the fourth
seam beginning from and ending at the second seam. In one exemplary embodiment, each
of the seams is semi-circular in plan view. In another exemplary embodiment when the
biocontainer is filled with a fluid, the biocontainer has a depth as measured between
the first and second walls, wherein the depth increases from each of the third and
fourth seams in a direction along each of the first and second seams transitioning
between minimum or no depth at each of the third and fourth seams to an expanded depth
at a distance from each of the third and fourth seams, wherein each of the fifth,
sixth, seventh and eight seams are located along a length within the distance. In
yet another exemplary embodiment, each of the fifth, sixth, seventh and eighth seams
are curved or define a geometric shape in plan view. In one exemplary embodiment,
each of the fifth, sixth, seventh and eighth seams intersects its corresponding first
or second seam at an external angle greater than 90°.
[0008] In any of the aforementioned exemplary embodiments, the biocontainer may include
a rod proximate at least one of said third and fourth ends or seams. Furthermore any
of the aforementioned exemplary embodiment biocontainers may be clamped proximate
its third and fourth sides or seams to an oscillating platform.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009]
FIG. 1 is a schematically depicted end view of a biocontainer mounted on a rocking
platform.
FIG. 2A is a top view of a biocontainer of the present invention.
FIG. 2B is a cross-sectional view taken along arrow 2B-2B in FIG. 2A of the biocontainer
shown in FIG. 2A in an inflated state.
FIGS. 3-11 are top views of an exemplary embodiment biocontainers of the present invention.
FIG. 12 is a partial cross-sectional view of another exemplary embodiment biocontainer
of the present invention.
FIG. 13 is a top view of another exemplary embodiment biocontainer of the present
invention.
FIG. 14 is a cross-sectional view of another biocontainer.
DETAILED DESCRIPTION
[0010] Applicants have invented a biocontainer bag that overcomes the deficiencies of the
current biocontainer bags. Applicants have been able to achieve this by including
relief sections in the transitional zones (Zones 2) 36, as for example shown in FIG.
3. The locations of the transitional zones for a given biocontainer dimensions may
be easily determined by filling the bag with a fluid. As discussed when the biocontainer
bag 10 is filled, the transitional zones 36 is the zone between the generally two-dimensional
flat end portions (Zone 1) 34 of the bag to the full three-dimensional center portion
(Zone 3) 38 of the bag. In an exemplary embodiment, four relief sections 37 are provided,
two extending from each of the weld lines 18 and 22, respectively. First relief sections
42, 46 are formed at the transitional zone proximate one end of the biocontainer and
second relief sections 44, 48 are formed at the transitional zone proximate the opposite
end of the biocontainer. Each relief section is formed by welding the two film sheets
together along the curve extending from its corresponding weld line 18, 22 (i.e.,
beginning from and ending at its corresponding weld line). Welding of such film sheets
is accomplished by using welding methods known in the art. In an exemplary embodiment,
each relief section has a semi-circular shape. In an exemplary embodiment, a semi-circular
shape has a radius not greater than one half of the length 51 of the transitional
zone 36 as measured along the weld lines 18 and 22. In another exemplary embodiment,
the bag may not be welded along any portion 51 of a section 50 between the beginning
and end of each relief section along each of the weld lines 18 and 20, as for example
shown in FIG. 4. In other exemplary embodiments as for example shown in FIG. 5, the
relief sections 37 may be formed by welding along a circular arc that is less than
a semi-circle. In another exemplary embodiment, the relief sections 36 may be formed
by welding along other geometric shapes, as for example an elliptical shape, or an
angular shape so as to form a triangle, or a free-flowing shape, or a rectangular
or square shape. In other exemplary embodiments as shown in FIG. 6, the interior of
the defined shape of the relief section may also be welded to define a solid shape,
as for example shape 37a. It is also desirable that an external angle 41 between the
weld lines 18 and 22, and the relief section is 90 degrees or greater. It is believed
that if the external angle is smaller than 90 degrees, as for example by forming a
relief section by welding along a circular arc which is greater than a semi-circle,
an area of intersection between the weld lines 18 and 22 and the relief section would
create an area where fluid stagnation can occur. Such stagnation can be detrimental
to the actual processing that the biocontainer needs to accomplish, such as mixing
or cell culture operations.
[0011] These relief sections in an exemplary embodiment provide for a biocontainer which
does not form any, or which has a reduced number of folds or crumples or other undesirable
film shapes when filled with a fluid. Applicants have discovered by eliminating or
reducing these folds, crumples or undesirable film shapes, the life span of the biocontainer
is increased. In addition, applicants believe that these relief sections cause a change
of direction in the fluid during the rocking motion. In other words, as the fluid
contacts these relief sections during the rocking motion, the fluid is caused to change
its direction and thus, better mix. As such, use of the inventive biocontainers result
in better processing of the fluid which is being processed within the biocontainer
during mixing or cell culture operations. Thus, another advantage of the present invention
is that the relief sections improve the mixing and processing accomplished by the
biocontainers. In this regard, the processing time required for processing such fluid
using the inventive biocontainers may be reduced.
[0012] In the exemplary embodiments where the relief sections are semi-circular, such sections
have a radius 56 that is proportional to the length (H2) 54 and the length 51 of the
transitional zone 36. However, applicants also believe that optimum length of the
radius 56 may also be affected by the ratio of the width 52 to the length 54. In an
exemplary embodiment, the location of a center 58 of each semi-circular relief section
is located at a distance 60 from an end 62 of the biocontainer bag from which end
the length 54 is measured. This distance 60 is also proportional to the length 54
but it is believed that it is also affected by the ratio of the width 52 to the length
54. In an exemplary embodiment, each relief section occupies at least a portion of
the length of the transitional zone. In another exemplary embodiment, each relief
section is confined within a transitional zone. Applicants believe that the distance
60 is at a maximum for square biocontainers, i.e., when biocontainers having a width
52 equal to the length 54.
[0013] In an exemplary embodiment relief sections, their dimensions and locations for a
22L biocontainer, a 50L biocontainer, and a 300L biocontainer, are shown in FIGS.
7, 8 and 9, respectively. The dimensions of the biocontainer and relief sections are
provided in inches, unless otherwise specified.
[0014] In another exemplary embodiment, either of the aforementioned relief zones 37 is
formed by welding or otherwise connecting the film sheets 16A, 16B together via another
member 90 such as a gusset or other piece of plastic as shown in FIG. 12. The gusset
or plastic may itself be a piece of film. This member is attached or welded to film
sheets 16A and 16B forming seams 92 and 94, respectively and limits the separation
of the upper wall and lower walls when the bag is filled with a fluid.
[0015] In another exemplary embodiment as for example shown in FIG. 10, applicants have
developed dual bag containers 80, 82 which are connected together along one weld line
84. In other words, both biocontainer bags 80, 82 share a common weld line 84. With
this invention, two different solutions may be oscillated using a single platform.
As can be seen, the inventive multiple compartment bags also designed to be used in
the existing platform, as for example by incorporating the rigid support rods 32 at
each end which are sealed into segregated areas 33 defined between weld lines. In
yet a further exemplary embodiment, any of the relief areas as described in relation
with the exemplary embodiment as shown in FIG. 3 may be incorporated in a multiple
compartment biocontainer, as for example shown in FIG. 11. Although the bag is being
shown with two compartments, the bag may be formed with more than two compartments
where adjacent compartments sharing a common weld line. In yet another exemplary embodiment,
the relief sections between each compartment can have different geometrical shapes
depending on the type of mixing or processing that is required.
[0016] Although the present invention has been described and illustrated with respect to
exemplary embodiments, it is to be understood that it is not so limited, since changes
and modification may be needed which are within the full scope of the invention. For
example, the biocontainer bags may have only two seams, as for example 20 and 24 (or
only seams 18 and 22 in another exemplary embodiment) plus the seams defining the
relief sections 37 as for example shown in FIG. 13. With this embodiment there are
no seams along the ends 96 and 98 of the biocontainer bag. In one embodiment the bag
may be formed to have a seam 100 along one of the upper portion or lower portion of
the film 16, as shown in FIG. 14 where the seam is formed on the lower portion. With
this exemplary embodiment, one end of the film 16 is welded or otherwise attached
to another end of the film 16 to form seam 100. As can be seen with these embodiments,
the biocontainers may be formed from a single film which is folded on to itself to
form the upper and lower films (or walls, or layers) of the biocontainer.
1. A biocontainer comprising:
a first flexible wall;
a second flexible wall opposite the first flexible wall;
a first end;
a second end opposite the first end;
a third end extending between the first and second ends;
a fourth end extending between the first and second ends and opposite the third end;
and
a first relief section extending from said first end, wherein said first relief section
is connects the first flexible wall to the second wall.
2. The biocontainer of claim 1, wherein the first relief section comprises a separate
member connected to the first flexible wall and to the second flexible wall.
3. The biocontainer of claim 1, wherein the first relief section is formed by connecting
said first flexible wall directly to said second flexible wall.
4. The biocontainer of any preceding claim, wherein the first relief section begins and
ends at the first end.
5. The biocontainer of claim 4, further comprising:
a second relief section, along which the first wall is connected to the second wall,
proximate the fourth end beginning from and ending at the first end;
a third relief section, along which the first wall is connected to the second wall,
proximate the third end beginning from and ending at the second end; and
a fourth relief section, along which the first wall is connected to the second wall,
proximate the fourth end beginning from and ending at the second end.
6. The biocontainer of claim 5, wherein when the bag is filled with a fluid, the biocontainer
has a depth as measured between the first and second walls, wherein the depth increases
from each of said third and fourth ends in a direction along each of said first and
second ends transitioning between minimum or no depth at each of the third and fourth
ends to an expanded depth at a distance from each of said third and fourth ends, wherein
each of said first, second, third and fourth seams are located along a length within
said distance.
7. The biocontainer of claim 6, wherein the expanded depth is a maximum depth.
8. The biocontainer of claim 5, wherein each of said first, second, third and fourth
relief sections are curved or define a geometric shape in plan view.
9. The biocontainer of claim 5, wherein each of said first, second, third and fourth
relief sections intersects its corresponding first or second end at an external angle
greater than 90°.
10. The biocontainer of any preceding claim, wherein when the bag is filled with a fluid,
the biocontainer has a depth as measured between the first and second walls, wherein
the depth increases from each of said third and fourth ends in a direction along each
of said first and second ends transitioning between minimum or no depth at each of
the third and fourth ends to an expanded depth at a distance from each of said third
and fourth ends, wherein said first relief section is located along a length within
said distance.
11. The biocontainer of claim 10, wherein the expanded depth is a maximum depth.
12. The biocontainer of any preceding claim, wherein a seam is defined along each of said
ends connecting the first flexible wall to the second flexible wall.
13. The biocontainer of any of claims 1 to 11, wherein a single piece of flexible material
is bent over itself and connected along a seam to form the first flexible wall and
the second flexible wall.
14. The biocontainer of claim 1, clamped to an oscillating platform proximate said third
and fourth ends.